The present invention relates to boat control devices and, in particular, to a sea anchor, also referred to as a drift anchor or drift sock, that has a resiliently biased leading edge and associated venting, flotation, weighting, retrieval and storage capabilities.
Varieties of sea anchors have been developed to control the drift and/or passive movement of watercraft. Each principally provides a conical or tubular body that tapers from a relatively large leading edge to a narrowed trailing edge. When tethered to a watercraft and drawn through the water, the anchor collects and displaces a volume of water that adds drag. The surface drift speed of the watercraft is thereby reduced.
U.S. Pat. No. 5,394,817 discloses a cylindrical drift anchor having control lines that control the exposed aperture of a trailing edge in a range from completely closed to fully opened.
U.S. design patent DES 329,220 discloses another conical, frustum shaped drift anchor having relatively small weights and floats distributed about the circumference of the leading edge. A draw tie at the trailing edge controls aperture exposure.
U.S. Pat. No. 4,534,306 discloses a tandem array of anchors secured to a common drag control line.
A further problem inherent to known drift anchors is the relatively long time it takes each to deploy in the water. That is, when dropped into the water, a certain amount of time is required for the leading edge of the drift anchor to become orientated and expand to a fully open condition. Prevailing winds, waves, boat motion, trapped air and fouled tether and retrieval lines can further delay the expansion of the anchor.
Drift socks have also been sold by Cabela's Corp. that attempted to solve this problem by providing a rigid hoop at the leading edge of the anchor. The hoop was constructed of a number of interconnecting segments that disassembled for storage. A principal deficiency of the anchor, however, was that the hoop segments were prone to break and kink, thereby necessitating continuous maintenance.
The present drift anchor was constructed to enhance the deployment rate of a drift anchor and overcome the deficiencies of predecessor anchors. The leading edge is particularly fitted with a flexible, resilient member that spring biases the leading edge to self-expand to an open condition. Associated, variable length tether lines, floatation, weighting and venting assemblies facilitate the self-orientation of the drift anchor. Retrieval guides contain a retrieval line and minimize line fouling.